The effect of laser surface treatment of titanium samples on the adhesive strength of adhesive joints

Abstract

The article considers the strength of adhesive joints of specimens made of OT-4 titanium alloys, the surface of which has been treated with laser radiation. The paper presents the results of the dependence of the macro- and microgeometry of the obtained surface, chemical composition, wetting angle and adhesion strength of adhesive joints under shear on laser processing modes. The purpose of this work is to determine the optimal parameters of laser processing for obtaining high strength adhesive joints. The results obtained can be used for gluing spacecraft structural elements. The studies were carried out on the adhesive pair «Titan – Titan». Depending on the processing mode, characteristic surface textures were identified, which were combined into groups «B», «K» and «C». High-energy modes of laser surface treatment of samples before gluing lead to a significant increase in the strength characteristics of the adhesive joint (up to 70 %) due to an increase in the area of the gluing surface and mechanical locking of the adhesive in the microrelief of the texture of the samples. In addition, the use of this method, in comparison with mechanical and chemical methods, significantly increases the productivity of surface treatment.